574 



Plate LXXX 



Fig. I. Illinois River levels, Havana. Monthly means, 1897-98 and 1909-10. 

 Fig. 2. Dissolved oxygen, Kankakee, upper Illinois, and Des Plaines rivers, 

 midsummer of 191 1. 



Plate LXXXI 



Fig. I. Dissolved oxygen Illinois River. November data. 



Fig. 2. Dissolved oxygen, Illinois River. Winter and midsummer data. 



Plate LXXXII 



Fig. I. Eristalis tennx, after Miall. 



Fig. 2a-2e. Hyalella knickerbockeri: 2a, entire animal; 2b, first cheliped ; 2c, 



first uropod ; 2d, second uropod ; 2e, telson, (U. S. Geol. and Geogr. 



Surv. of the Territories, 1873.) 

 Fig. 3. Slime worms, Tubifex, after Kolkwit?:. 

 Fig. 4. Rotifer actinurus, after Kolkwitz. 

 Fig. 5. Colpidiuni colpoda, after Kolkwitz. 

 Fig. 6. Paramecium putrinum, after Kolkwitz. 



Plate LXXXIII 



Fig. I. Paramecium caudatu»i, after Blochman. 



Fig. 2. Vorticella microstoma, after Blochman. 



Fig. 3. Epistylis plicatilis, after Blochman. 



Fig. 4. Carchcsium lachmanni, after Kent. 



Fig. 5. A)ithopliysa '7'egetans, after Blochman. 



Fig. 6. Anthophysa vegetans, after Kent. 



Fig. 7. ChlaiHydomonas monadina, after Blochman. 



Fig. 8. Oikomonas ternio, after Blochman. 



Fig. 9. Bodo saltans, after Kolkwitz. 



Fig. 10. Stigeoclonium tcnue, after Kirchner. 



Plate LXXXIV 



Fig. I. Chcctophora elegans. 



Fig. 2. Microthamnion kittzingianum, after Kirchner. 



Fig. 3. Cladophora crispata, after Kolkwitz. 



Fig. 4. Cladophora glomerata, after Kolkwitz. 



Fig. 5. Schi::omeris leibleinii. Tufts College Studies. Vol. II. 



Fig. 6. Ulothrix sonata. 



Fig. ya-ye. Chlorella vulgaris. Rev. Gen. Botanique, Tome XV. 



Fig. 8. Lyngbya versicolor. Minn. Algae, Vol. I. 



Fig. 9. Phormidium uncinatum. Minn. Algse, Vol. I. 



Fig. 10. Oscillatoiia liinosa, after Kolkwitz. 



Plate LXXXV 



Fig. I. Cyclotella kiltzingiana, after Kirchner. 

 Fig. 2. Fragilaria virescens, after Kirchner. 

 Fig. 3. Tabellaria Hocculosa, after Kolkwitz. 

 Fig. 4. Tabellaria fenestrata, after Kirchner. 

 Fig. 5. Mclosira varians, after Kolkwitz. 

 Fig. 6a, 6b. Sphceroiilus nutans, after Kolkwitz. 

 Fig. ya, yc. Cladothrix dicJwtoma. after Kolkwitz. 

 Fig. yb. Cladothrix dichtoma, after Kirchner. 

 Fig. 8. Beggiatoa alba, after Kolkwitz. 



